Cord-winding structure



June 23, 1964 R. DESCARRIES 3,137,883

CORD-WINDING STRUCTURE Filed April 1, 1958 INVENTOR.

Larry/m5) June 23, 1964 R. DESCARRIES CORD-WINDING STRUCTURE 5 Sheets-Sheet 2 Filed April 1, 1958 INVENTOR. fa /MW! fil/W BY June 23, 1964 R. DESCARRIES 3,137,883

CORD-WINDING STRUCTURE Filed April 1, 1958 5 Sheets-Sheet 3 llil i i i INVENTOR. gay/km! fill W Q/ZW June 23, 1964 R. IDDESCARRIES 3,137,883

CORD-WINDING STRUCTURE Filed April 1, 1958 5 Sheets-Sheet 4 hi? 7 Z? June 23, 1964 R. DESCARRIES CORD-WINDING STRUCTURE 5 Sheets-Sheet 5 Filed April 1, 1958 United States Patent 3,137,883 CORD-WINDING STRUCTURE Raymond Descarries, Montreal, Quebec, Canada, assignor toAktiebolaget'Electrolux, Stockholm, Sweden, a corporation of Sweden Filed Apr. 1, 1958, Ser. No. 725,732 16 Claims. (Cl.-,15-323) My invention relates to electric cord-winding structure and is especially concerned with an electric cord-winding structure for use with a suction cleaner of the type employing a dust bag within a shell or casing.

It has already been proposed to provide electric cordwinding structure in an end cover of a suction cleaner casing in which a dust bag is .disposed, the end cover having an air passageway terminating in an outlet from which air is discharged from the cleaner. Ina construction of this kind, an electric cord is adapted to be wound with the ing a central opening to accommodate an air passageway must be substantially longer and formed with a greater number of turns in order to obtain a motor spring having torque characteristics comparable to those of a spiral spring which can be wound tightly from the immediate vicinity of its inner end about a shaft of relatively small diameter.

An object of my invention is to provide an improved electric cord-winding structure of this type in which an electric cord is adapted'to be wound on a rotatable reel having a hollow hub-like part through which the air passageway extends, and to effect winding of the cord on the reel with the aid of a spiral spring having a relatively small inner diameter which is substantially less than that of the air passageway. I accomplish this by winding the cord on the rotatable reel with the aid of a motor spring of spiral form which is eccentrically disposed with respect to the reel.

Another object of my invention is to provide an improved electric cord-winding structureof this type having a spiral spring which is eccentrically disposed with respect to a rotatable reel upon which an electric cord may be wound by transmitting torque to the reel from the spring with the aid of suitable mechanism like gearing,

for example.

A further object of my invention is to provide an improved electric cord-winding structure of this'type having a constant torque motor spring to transmit torque for winding an electric cord on a rotatable reel, the spring being adapted to be spirally wound on a first spool eccentrically disposed with respect to the reel and having one end thereof connected to a second spool concentric with and forming a unitary part of the reel.

A still further object of my invention is to Provide an improved electric cord-winding structure of simplified construction which can be readily assembled.

A still further object of my invention is to provide an improved electric cord-winding structure and suction cleaner end cover or closure constructed as a single unit in such a manner that the cord-winding structure parts are compactly arranged in the cover or closure and accurately aligned therein to facilitate completing an electric circuit for the suction cleaner motor when the end cover is moved to its closedposition.

Further objects andadvantages of the invention will becomeapparent as the following description proceeds, and the features of novelty which characterize the invention will be pointed out with particularity in'the claims annexed to and forming a part of this specification.

For a better understanding of the invention, reference maybe had to the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a side view of a suction cleaner embodying the invention;

FIG. 2 is an end view of the cleaner illustrated in FIG. 1;

FIG. 3 is an enlarged longitudinal sectional view of an end of the cleaner'shown in FIGS. 1 and 2;

FIG. 4 is asectional view of parts shown in FIG. 3'to illustrate details more clearly;

FIG. 5 is a transverse sectional view taken at line "55 of FIG. 3;

FIG. 6 is a transverse view, partly broken away and in section, taken at line 6-6 of FIG. 3;

FIG. 7 is a sectional view taken at line 77 ofFIG. 6;

FIG. 8 is a view, partly broken away and in section, :of anend of the cleaner illustrated in FIGS. 1, 2 and 3 to show a different position of the parts;

FIG. 9 is a side view of parts shown in FIGS. 3 and .4 to illustrate details;

FIG. 10 is a'longitudinal sectional view of an end of a cleaner illustrating another embodiment of the invention;

FIG. 11 is a transverse sectional View taken at line 11-11 of FIG. 10;

FIG. 12 is a transverse sectional view taken at line 1212 of FIG. 11; and

FIG. 13 is a fragmentary sectional view taken at line 1313 of FIG. 12.

Referring to the drawings, the invention has been shown in connection with a horizontal tank-type suction cleaner 10 comprising a casing 11, a front end cover 12 and rear end cover 14. The casing 11 is provided with a'handle 15 and wheels 16 and 17 to facilitate movement thereof on a supporting surface, the single wheel 16 at the front end of the casing being centrally disposed between the .side walls of the cleaner and rotatable about a vertical axis, as shown in FIG. 2.

The front end cover 12, which is removably secured to the casing 11 in any suitable manner, is formed with an inlet 18 to which a suction hose (not shown) is adapted to be removably connected. Suitable cleaning appliances may be connected to a wand which in turn is connected to the outer free end of the suction hose and through which air flows into the casing at the front end of which is disposed a dust bag 19 in which dirt is collected.

Flow of air through casing 11 is effected by a motorfan unit 20 which includes a centrifugal fan 21 carried at one end of an electric motor 22 resiliently mounted in any suitable manner at 23 within the casing 11. The fan 21 receives air which passes through the dust bag 19 and is substantially free of dust and dirt, such air being discharged from the fan through the motor 22 and eventually passing through an opening '24 in the end cover "14. The motor 22 is connected by conductors 25 to an electric switch 26 which is arranged to be actuated by a movable member 27 located at thetop of the casing 11.

The casing 11 is provided with anend ring 28 having a U-shaped groove 29 about the periphery thereof which receives an end edge of the casing, the latter beingembedded in suitable sealing material 30 to provide-an airtight joint. An apertured transverse wall 31, which may be formed integrally with the end ring 28, is-disposed at the end of casing 11 adjacent to the motor 22. The end ring 28 and transverse wall 31 may be secured'to thetcasing 11 in any suitable manner. As shown-in FIG. :3, the

casing 11 may be provided with a reinforcing rib or flange 32 having threaded openings to receive the ends of fastening screws or bolts 33 passing through openings in the transverse Wall 31.

The end ring 28 is formed with a pair of downwardly projecting lugs 34 having openings in which are journaled stub shafts 35 to which the wheels 17 are fixed. The rear end cover 14 is provided with a pair of. spaced apart arms 36 at the bottom thereof, the arms projecting downwardly and also toward the casing 11, as best shown in FIG. 3. The lower ends of the arms 36 are pivotally mounted on the stub shafts 35 to provide a hinge connection of the rear end cover 14 to the end of the casing 11, as seen in FIGS. 2, 3 and 8.

The rear end cover 14 includes a cup-shaped member 37 having the opening 24 in an end wall at the closed end thereof from which a tube or hollow sleeve-like member 38 extends toward the air inlet end of the casing 11. The end cover 14 is provided with an end wall or closure plate 39 having a rim portion 39a perpendicular to the longitudinal axis of the cleaner, an inwardly extending dished portion 39b and a notched inner peripheral edge portion 39c which receives the inner end of the sleeve-like member 38. The cup-shaped member 37 and closure plate 39 therefor are removably secured together in any suitable manner. As shown in FIG. 3, the bottom part of the member 37 may be notched to receive a pair of lugs 40, one of which is illustrated, which project downwardly from the plate 39 to provide a loose pivotal connection for the plate. With the lugs 49 located in the notches therefor, the top part of the cover 39 may be removably secured to the cup-shaped member 37 by one or more screws 41.

The apertured transverse wall 31 is provided with an opening 42 to receive the threaded end of a bolt 43 for removably securing the rear end cover 14 to the casing 11, as shown in FIG. 3. The bolt 43 is held in a hollow tubular member 44 from which extend radially spaced apart ribs 45 whose outer ends are fixed to the hollow sleeve-like member 38. The head 43a of bolt 43, which is wing-shaped to facilitate connecting and disconnecting the rear end cover 14 to and from the casing 11 without the use of tools, is disposed within the opening or outlet 24 at which region the hollow member 33 may be formed with a circular recess 46 to detachably receive an end of a suction hose or appliance making use of a stream of air discharged from the suction cleaner 10.

The hinge connection of the rear end hood 14 to the casing 11 provides a convenient construction for inspecting and changing, when necessary, a fine dust filter 47 which is held in position between the apertured transverse wall 31 and the rear end cover 14, as shown in FIG. 3. The peripheral edge portion of the filter 47 is clamped in an air-tight manner between a raised ledge 31a of the transverse wall 31 and the peripheral edge portion 39a of the closure plate 39 of the rear end cover 14. The filter 47 is held in place and prevented from flexing toward the discharge opening 24 by a plurality of spaced apart fins r bafiles 48 which are fixed to the dished portion 39b of the closure plate 39. A number of channels are formed between the fins 48 through which air, after passing through the filter, flows through the hollow sleeve-like member 38 and is discharged at the outlet 24. Thus, the closure plate 39 and apertured wall 31 are constructed and arranged to removably hold the filter pad 47 about its periphery in airtight sealing relation therewith along a line defining a zone which is transverse to the longitudinal axis of the cleaner and is completely enveloped and concealed from view by the casing 11 and rear end cover with the latter in closed position.

In FIG. 3 it will be seen that the bolt 43 for connecting the end cover 14 to the casing 11 is provided with a washer 43b which is fixed thereto and axially movable between the inner end of the tubular member 44 and a small hub-like part 39d of closure plate 39 to which the inner ends of the bafiles 48 are secured. Hence, the hublike part 39d and tubular member 44 limit axial move ment of the tightening bolt 43 on the end cover 14 and hold the bolt in the end cover when the latter is disconnected from the casing 11, as shown in FIG. 8.

In accordance with this invention, a reel 49 is rotatably mounted on the hollow sleeve-like member 38 of the end cover 14 and held in position thereon by the closure Plate 39. As best shown in FIG. 4, the reel 49 comprises a pair of cooperating parts 50 and 51, the part 50 being formed of any suitable insulating material which is relatively hard. Each of the parts 50 and 51 forms a side wall of the reel 49 and also a portion of the hub thereof, the hub portions being held together by a hollow bushing 52 having outwardly bent flanges, as seen in FIG. 3. The inner end part of the hollow sleeve-like member 38 is of reduced diameter and receives the flanged bushing 52 which is held in position in the notched region 53 of the hollow member 38 and inner peripheral edge portion 39c of the closure plate 39.

About the reel 49 is adapted to be wound an insulated electrical cord 54 at the outer end of which is fixed a conventional plug 55 for connecting the cord to a suitable source of electrical supply. An opening 56 is formed in a side wall of the rear end cover 14 through which the cord 54 is adapted to pass, the opening being of such size and shape relative to the plug 55 that the latter is held at the opening and cannot pass therethrough into the end cover 14 when the cord is released and the cord is being Wound on the reel.

The hub portion of the insulated reel part 50 is formed with a circular groove 57 which receives the inner end portion of the electrical cord 54. At the vicinity of the groove 57 the reel part 50 is provided with an opening 58 through which the insulated conductors 54a and 54b of the cord 54 extend to the outer face of the reel part 50. As best shown in FIG. 9, the cord 54 is positioned in the groove 57 through an arc of about 180, the outer groove wall at the region the cord leaves it having an opening 57' through which the cord passes. With this arrangement, the part of the cord 54 in the groove 57 always remains therein when the cord is fully unwound from the reel. When the cord is subjected to an exceptionally heavy pulling force under these conditions, the full force cannot be transmitted to the ends of conductors 54a and 54b but instead is taken up by the arcuate-shaped portion of the conductor 54 positioned in the groove 57 which serves as a strain relief.

As best seen in FIGS. 3 and 5, the extreme outer bare end of conductor 54a is connected to an inwardly extending tab 59 of a slip ring 60 which is positioned in a circular recess 61 formed in the outer surface of the reel part 50, and the extreme outer bare end of conductor 54b is connected to the inner end of a longer insulated tab 62 which is formed on a slip ring 63 which is disposed about the slip ring 60 and positioned in a circular recess 64 formed in the outer surface of the reel part 50.

The slip rings 66 and 63 and tabs 59 and 62 forming a part thereof may be stamped from brass sheeting, for example, to provide an inexpensive slip ring construction, the tab 62 initially extending radially outward from the slip ring 63 and being bent back and extending radially inward toward the hub of the reel 49 when positioned on the reel part 50, as best shown in FIG. 3. At spaced apart intervals about the circular recesses 61 and 64 of the reel part 50 are formed notches 65, as seen in FIG. 4. Alternate notches 65 in each recess are provided at the inner and outer peripheral edge portions of the recesses and receive tabs 66 formed on the slip rings 6%) and 63. The tabs 66 pass through the notches 65 and are bent to hold the slip rings in positron in the reel part 56, the latter being formed with cavities or depressed regions 67 at the inner wall surface opposite the notches 65 to receive the bent tabs 66 which will then be essentially flush with the inner'wall surface of the reel part 50.

It will be understood, of course, that the tabs 66 may be formed on the slip rings 60 and 63 when the latter are stamped from brass sheeting, for example, such tabs being in the planes of the slip rings when initially formed and then bent at right angles to the rings prior to inserting them through the notches 65. Hence, all of the tabs 59, 62 and 66 may be formed integrally with the slip rings 60 and 63 when the latter are stamped from metallic sheeting.

The closure plate 39 for the end cover 14, which desirably is formed of a suitable plastic material possessing electrical insulating properties, is formed with an arm or projecting part68 at the top part thereof which is apertured at 69 and receives a pair of electrical connecting elements 70 and 71, respectievly, as best shown in FIGS. and 8. To the electrical connecting elements 70 and 71 are connected downwardly extending resilient leaf springs 70a and 71a having contact buttons at their lower ends which are in good intimate contact with the slip rings 63 and 60, respectively. The connecting elements 70 and 71 and leaf springs 70a and 71a are formed and constructed so that the latter are effectively biased toward the slip rings 63 and 60 to provide a good electrical connection between these parts.

As seen in FIGS. 3 and 8, a member 72 fixed to the top part of casing 11 at 73, at the vicinity of the transverse end Wall 31, is formed with a cavity or recess 74 which receives the arm or projecting part 68 when the end cover .14 is connected to the casing 11. In the cavity 74 are positioned alongside one another a pair of electrical connecting elements 75, one of which is illustrated in FIG. 8. The elements 75, switch 26 and motor 22 are connected in series relation in any suitable manner (not shown) so that, when the end cover 14 is moved from the open position of FIG. 8 to the closed position of FIG. 3 and the con necting plug 55 is connected to a source of electrical supply, the contacts 70 and 71 on the end cover 14 engage the contacts 75 on the casing and a circuit will be completed for the motor 22 when the member 27 is moved to close the switch 26. In view of the foregoing, it will be understood that the circuit completed for the motor 22 will include the conductors 54a and 54b of the electrical cord 54, the slip rings 60 and 63 and the resilient leaf contacts 70a and 71a associated with the electrical contacts 70 and 71, respectively.

In accord with the invention, the electrical cord 54, when released, is wound on the reel 49 with the aid of a spring motor 76 which includes a spring 77 of spiral form which is eccentrically disposed with respect to the reel. The spiral-shaped spring 77 is positioned within a cavity or chamber 78 formed by a wall 79 of annular form which is integral with the end cover 14 and extends axially inward from the closed end of the cup-shaped part 37 thereof. As seen in FIG. 7, the wall '79 at one region 79a merges with the hollow sleeve-like member 38 of the end cover.

The inner end of the spring 77 is secured at 80 to a stud 81 which is rotatable about a fixed axis and journaled .at one end in an opening 82 formed in the closed end of .edge of the opening 85.

To the portion 81a of the stud 81 which is disposed outside the cover plate 83 is rigidly fixed a gear 86 which isin mesh with a second gear 87 rotatable with the reel 49 and forming a unitary part thereof. As shown in FIGS.'6 and 7, the gear 86 may be formed with a squaree shaped central opening to receive the end portion 81a of the stud 81 which may be of similar shape. If desired, the second gear 87 may be provided on the part 51 of the rotatable reel 49, as best shown in FIG. 4. As seen in FIG. 3, the gears 86 and 87 are disposed between the side wall-51 of the cord reel 49 and the front of the spring motor 76. The side 51 of the reel 49 and the end wall of cover 14 having the outlet 24 define an axially extending end space 37a in the member 37 which is disposed about the tube 38 and into which projects a part of the hub of reel or rotatable element 49 to which the gear 87 is fixed.

When the parts thus far described are in theposition shown in FIGS. 3, 5, 6 and 7, the cord 54 is wound about the reel 49 and the connecting plug 55 is held at the opening 56 of the rear end cover 14 by the action of the spring 77. When the plug 55 is pulled to unwind the cord 54 from the reel 49, the tension of the elongated flat spring 77 increases, because the rotating movement of the reel is transmitted by the gears 87 and 86 to the stud 81. In effect, the reel 49 and stud 81 rotate in unison with unwinding of the cord 54 from the reel, which results in increasing the tension of the spring 77. When the plug 55 is subsequently released, rotating movement is imparted to the reel 49 by the spring 77 which is under considerable tension, such rotating movement being transmitted to the reel from the spring through the gears-86 and 87. Under these conditions, the released cord 54 is wound on the reel 49 until the connecting plug 55 engages the rear end cover 14 at the immediate vicinity of the opening 56 through which the cord passes.

A pawl and ratchet mechanism is provided to render the spring motor 76 inelfective to impart rotating movement to the reel 49 when substantially all or any part of the cord 54 has been unwound from the .reel 49 and the spring 77 is under tension. .such mechanism comprises a number of pawls 88 which are pivotally mounted at 89 to the outer face of the insulating reel part 50. Each pawl 88 is positioned in a recessed or notched portion 90 of arcuate shape having an .upstanding wall 91 extending in a clockwise direction from the point 91a to the point 91b. The outer end of each pawl is formed with a finger 92 adapted to en- .gage any one of several notches 93 formed atthe exterior surface of the inner peripheral edge portion 390 of the closure plate 39 for the end cover. When the cord 54 is being unwound from the reel 49 and the latter is being rotated, the pawls 88 move in a counter-clockwise direction in FIG. 5. With the suction cleaner in a normal upright position during such movement of the reel 49, the two bottom pawls 88 move by gravity from the bottom notches 93. As each pawl moves past the top notch 93 it may momentarily move therein and immediately continue its counter-clockwise movement.

Let us assume that a part of the cord 54 has been unwound from the reel 49 and the pawls88 are in-the positions shownin FIG. 5. Under these conditions, the

top pawl 88 engages the top notch and renders the spring 77, which is under tension, ineifective to impart clockwise movement to the reel. When it is desired to wind the cord 54 on the reel 49, the cord is pulled from the reel for 'a short distance and then released. Under these conditions, rotating movement is imparted to the reel 49 in a clockwise direction in FIG. 5 under the action of the spring 77, such movement being suiiicient to cause the pawls 88 to move outwardly against the wall 91 by centrifugal force and remain out of engagement with all of the notches 93.

The pivotal connection "89 of each pawl 88 to the reel part 50 includes a raised cylindrical portion or stud which receives the 'apertured end of the pawl. A washer 89a .is provided at each pivotal connection which overlies the outer faceof 'the pawl and holds the latter in position,

as shown in FIG. 3. It will be seen that a certain amount of play 89b is provided between the opening in each As shown in FIG. 5,

pawl and the stud in which it is seated. This loose connection is provided so that, when one of the pawls engages a notch 93 to render the spring 77 ineifective to impart rotating movement to the reel, such as the top pawl in FIG. 5, for example, the pawl can move on the pivotal connection 89 until it bears against and is in intimate contact with the upstanding wall g1 at the region 910 thereof. In this way all of the force to hold the reel 49 stationary will be transmitted directly through the pawl from the upstanding wall 91 of the reel part 56 to the closure plate 39 at the region of the notch 93 therein, and the pivotal connection 89 of the pawl will not be required to transmit any force and will simply serve to hold the pawl in position in the insulating reel part 56'.

A number of pawls 83 and notches 93 are provided so that, irrespective of the position of the suction cleaner, whether it is upright or on its side or in any other position, at least one of the notches 93 will always be effective to engage a pawl 88 when it is desired to render spring 7'7 ineffective to impart rotating movement to the reel 49 and wind the cord 54 thereon.

Another embodiment of the invention is illustrated in FIGS. 10 to 13, inclusive, which differs from the firstdescribed embodiment in that an electrical cord 154, when released, is wound on a reel 149 with the aid of a constant-torque spring motor 176. In FIG. 10, which is a view similar to FIG. 3 of the first-described embodiment, the rear end cover 114 includes a cup-shaped member 137 provided with a pair of spaced apart arms 136 for pivotally connecting the end cover to the end of the cleaner casing.

The cup-shaped member 137 includes a hollow sleevelike part 138 which extends from the opening 124 at the closed end thereof to a closure plate 139. The closure plate 139 is formed with an outer rim portion 139a, an intermediate dished portion 13%, and a notched inner peripheral edge portion 1390 which receives the inner end of the sleeve-like part 138. The bottom part of the member 137 is notched to receive a pair of lugs 140, one of which is illustrated, which project downwardly from the plate 139 to provide a loose pivotal connection therefor. With the lugs 14% located in the notches therefor, the top part of the cover 139 may be removably secured to the cup-shaped member 137 by one or more screws 14]..

As in the first-described embodiment, the cup-shaped member 137 is formed with a hollow tubular member 144 from which spaced apart ribs 145 extend radially outward and are fixed at their outer ends to the hollow sleeve-like part 138. The threaded bolt (not shown) for securing the end cover 14 to the cleaner casing passes through the tubular member 144 and the small hub-like part 139d of the closure plate 139, the intermediate portion 13% of which is provided with baffles 148 against which a face of a fine dust filter is adapted to bear, as described above and illustrated in FIG. 3.

The reel 149 differs from the reel 49 described above in that the spaced apart side walls 150 and 151 and connecting hub 149a may be formed integrally with one another. The side wall 150 may be formed with a central depressed portion which receives an insulating member 150a of annular form upon which the slip rings 16% and 163 are fixed. The insulating member 156:1 is formed with a semi-circular groove 157 which receives the inner end portion of the electrical cord 154 to obtain relief from strain in the same general way shown in FIG. 9 and described above. As best shown in FIG. 10, the inner bare ends of conductors 154a and 1S4b are connected to the slip rings 169 and 163 with which the leaf springs 170a and 171a are in good intimate contact. Although not shown in FIG. 10, it will be understood that in the embodiment being described the leaf springs 170a and 171a are connected to a pair of electrical connections in the arm 163 at the top part of the end cover 114 in the same way illustrated in F168. and 8 and described above.

In FIG. 10 the insulating member 1590, which forms the inner part of side wall 150, is provided with cavities or depressed regions 167 at its inner wall surface, the cavities opposite the inner slip ring being formed at the bottom of the semi-circular groove 157. Notches 165 extend through the insulating member 150a to the cavities 167 from the vicinity of each groove in which the slip rings 165) and 163 are positioned. The notches receive the tabs 166 on the slip rings 16! and 163, the ends ofthe tabs being bent and bearing against the bottoms of the cavities 167 to secure the slip rings to the insulating member 1556a. A layer 15% of insulating material overlies the inner face of insulating member 15% at the region the conductor 15 2b is connected to the tab 166 at the outer slip ring 163. It will be evident that the slip rings lot) and 163 are fixed to the insulating member 153a in a manner similar to the way the slip rings 50 and 63 are mounted on the insulating wall 50 in the first-described embodiment.

From the side wall 151 of the reel 1 .9 extends a hollow sleeve-like section 187 having at its outer end an outwardly extending side or flange 1530 formed with a rim or collar 191 at the outer peripheral edge thereof. Hence, the side 151 of the reel 149 and the end wall of the member 137 having the outlet 124 define an axially extending end space 13711 into which the part 187 projects. As seen in FIG. 10, the reel 149 is journaled on the hollow sleeve-like part 133 by flanged bushings 152a and 1525, the closure plate 139 serving to hold these parts in position on the sleeve-like part 133.

The flange 1% is provided with a number of hollow studs, each of which receives the apertured end of a pawl 188. Washers 189a are positioned over the pawls 188 by pins 189 to hold the pawls in position, as best shown in FIG. 10. The outer end of each pawl 188 is formed with a finger 192 adapted to engage any one of several notches 193 formed at the exterior surface of the hollow sleeve-like part 133 at the immediate vicinity of the closed end of the end cover 114. The operation of the pawl and ratchet mechanism illustrated in FIGS. 10 and 11 and just described is substantially the same as that of the pawl and ratchet mechanism illustrated in FIGS. 3 and 5 and described above and will not be repeated here.

Within the closed end of the cup-shaped member 137 is provided a hollow boss 182 within which is fixed a collar 182a which is threaded to receive a stud 181 for supporting a pulley 94 for rotation thereon about a fixed axis. About the pulley 94 is spirally wound an elongated fiat spring 177 of a constant-torque type, the outer end of which is extended and anchored at 95 to the hollow sleeve-like section 187 of the reel 149. The constanttorque spring 177 may be of the kind like that available under the trade mark Negator and generally disclosed in United States Patents Nos. 2,609,192 to B. Lerrnont and 2,647,743 to W. J. Cook.

When the hollow sleeve-like section 187 of the reel 149, which may be referred to as an output spool, is being rotated, as when the electrical cord 154 is being unwound from the reel, successive portions of the spring 177 are transferred from the pulley or spool 94 to the spool 187. When such movement is imparted to spring 177, the spring initially moves in an essentially straight path at a region 177' and then bends backwards about the spool 187. The spring 177, which is prestressed, possesses such physical properties that, during rotation of the spool 187, the part of the spring already transferred to this spool does not undergo any change in stress, while the part of the spring on the spool 94 is substantially unstressed. Only that part of the spring 177 moving through the region or zone 177 is subject to and undergoes a change in stress. Due to this physical property inherent in the spring 177, successive longitudinal portions of the spring during winding or unwinding are progressively stressed incrementally in a substantially non-cumulative manner. Therefore, from the beginning to the end f a driving cycle the torque produced by the spring motor 176 is substantially constant by reason of the pull of the extended part of the spring 177 at the periphery of the spool 187 plus the added torque pro duced by the bending moment required to bend back the straight section 177' to conform to the curvature of the spool .187.

When the cord 154 is pulled to unwind it from the reel 149, rotating movement is imparted to the spool 187 and reverse winding of the spring 177 thereon is effected, the spring being stressed sequentially in increments. When the cord 154 is subsequently released, the spring 177 is transferred from the spool 187 to the spool 94, the torque developed by the spring being substantially constant during the entire cycle during which the cord 154 is being wound on the reel 149.

It will be noted that the diameter of spool 94 is smaller than that of spool 187. While the extended end of the spring 177 is fixed at 95 to the larger spool 187, the inner end of the spring is free of and not attached to the spool 94 which desirably may be formed of a suitable plastic material and freely rotatable on the stud 182.

In view of the foregoing, it will now be understood that an improved electrical cord-winding structure has been provided having a compact arrangement of parts and which is relatively light in weight. In each of the embodiments illustrated and described, a spring motor is effectively employed to transmit movement to a cord reel with the aid of a spring which is spirally disposed about a rotatable part which is eccentrically positioned and fixed with respect to the axis of the rotatable reel. In the embodiment of FIGS. 1 to 8 the torque developed by the spring 77 is transmitted from the spring to the reel 49 with the aid of gears-86 and 8'7 operatively associated with these parts. In the embodiment of FIGS. 10 to 14 the substantially constant torque developed by the spring 177 is transmitted to the reel by anchoring fthereto at '95 the outer extended end of the spring. In each embodiment a simple construction is obtained in which an air passageway extends through a hollow hub portion of the reel, so that air passing through the suction cleaner may be discharged therefrom from an outlet at the closed end of the rear end cover within which the electrical cord-winding structure is disposed. This produces an inexpensive and easily manufactured construction.

While particular embodiments of the invention have been shown and described, such variations and modifications are contemplated as fall within the true spirit and scope of the invention, as pointed out in the following claims.

What isclaimed is:

1. In apparatus of the class described, a hollow casing having spaced end walls, the end walls respectively having an inlet and an outlet for air, means comprising a stationary hollow'tube having one end joined to the casing 'at the outlet and extending within said casing toward the inlet, said tube defining at least a portion of an air passageway between the inlet and the outlet, a hollow rotatable element, a reel forming a part of said rotatable element and having spaced sides, means for mounting said hollow element on said tube for rotation thereon about a first stationary axis with said reel spaced from the end wall having the outlet, one of the sides of said reel and the end wall having the outlet defining an axially extending end space in said casing which is disposed about said tube and into which apart of said hollow element projects,

"an electrical cord for said reel which may be wound structureinc'luding a rotatable member, means at the end wall having the outlet for mounting said member for 1t) rotation in said endspace about a stationary second axis spaced from and substantially parallel tothe first axis about which said hollow element rotates, and an elongated flat spring wound on said rotatable member;

2. In apparatus of the class described, a hollow casing having spaced end walls, the end walls respectively having an inlet and an outlet for air, means comprisinga stationary hollow tube having one end joined to the casing at the outlet and extending within said casing toward the inlet, said tube defining at least a portion of an air passageway between the inlet and the outlet, a hollow rotatable element, a reel forming a part of saidrotatable element and having spaced sides, means for mounting said hollow element on said tube for rotation thereon about a first stationary axis with said'reel spaced from'the end wall having the outlet, one of the sides of said reel and the end wall having the outlet defining an axially extending end space in said casing which is disposed about said tube and into which a part of said hollow element projects, an electrical cord for said reel which may be wound thereon between its spaced sides, and structure operatively associated with the projecting part of said hollow element to impart rotating movement to said element and said reel for winding the cord thereon, said last-mentioned structure including a rotatable member, means at the end wall having the outlet for mounting said member for rotation in said end space about a stationary second axis spaced from and substantially parallel to the first axis about which said hollow element rotates, and a flat elongated constant torque spring wound on said rotatable member and having its outer end connected to the projecting part of said element.

3. In apparatus of the class described, a hollow casing having spaced end walls, the end walls respectively having an inlet and an outlet for air, means comprising a stationary hollow tube having one end joined to the easing at the outlet and extending within said casing toward the inlet, said tube defining at least a'portion of an air passageway between the inlet and the outlet, a hollow rotatable element, a reel and a first spool forming parts of said rotatable element and each having spaced sides, means for mounting said hollow element on said tube for rotation thereon about a first stationary axis with said reel spaced from the end wall having the outlet, one of the sides of said reel and the end wall having the outlet defining an axially extending end space in said casing'which is disposed about said tube and in which said first spool is positioned, an electrical cord for said reel which may be wound thereon between its spaced sides, structure operatively associated with said first spool of said hollow element to impart rotating movement to said element and said reelfor winding the cord thereon, said last-mentioned structure including a second spool and means at the end wall having the outlet for mounting said second spool for rotation in said end space about astationary second axis spaced from and substantially parallel to the first axis about which said hollow element rotates, and a flat elongated prestressed spring wound on said second spooland having its outer end connected to said firstspool.

4. Apparatus as set forth in claim 3 in whichthe diameter of said first spool is larger than that of said second spool, said second spool having at least one side with its outertperiphery projecting into the gap between the sides of said first spool, mechanism including a pawl and a notch for rendering said structure operatively associated with said first spool ineffective to impart rotating movement to said element and said reel, means pivotally mounting said pawl on the side of said first spool next to said end wall having the outlet, and said notch being formed on a stationary part within said casing.

5. Apparatus as set forth in claim 3 in which said one side of said reel serves as a side of said first spool, said second spool having at least one side with its outer periphery projecting into the gap between the sides of said first spool, mechanism including a pawl and a notch for rendering said structure operatively associated with said first spool ineffective to impart rotating movement to said element and said reel, means pivotally mounting said pawl on the outer face of the side of said first spool next to said end wall having the outlet, and said notch being formed on a stationary part within said casing.

6. Apparatus as set forth in claim 3 which comprises mechanism including a pawl and a notch for rendering said structure operatively associated with said first spool ineflective to impart rotating movement to said element and said reel, means pivotally mounting said pawl on the outer face of the side of said first spool next to said end wall having the outlet, and said notch being formed on a stationary part within said casing.

7. In apparatus of the class described, a hollow casing having spaced end walls, the end walls respectively having an inlet and an outlet for air, means comprising a stationary hollow tube having one end joined to the casing at the outlet and extending Within said casing toward the inlet, said tube defining at least a portion of an air passageway between the inlet and the outlet, a hollow rotatable element, a reel forming a part of said rotatable element and having spaced sides, means for mounting said hollow element on said tube for rotation thereon about a first stationary axis with said reel spaced from the end wall having the outlet, one of the sides of said reel and the end wall having the outlet defining an axially extending end space in said casing which is disposed about said tube and into which a part of said hollow element projects, an electrical cord for said reel which may be wound thereon between its spaced sides, and structure operatively associated with the projecting part of said hollow element to impart rotating movement to said element and said reel for winding the cord thereon, said last-mentioned structure including a rotat able member, means at the end wall having the outlet for mounting said member for rotation in said end space about a stationary second axis spaced from and substantially parallel to the first axis about which said hollow element rotates, an elongated flat spring Wound on said rotatable member with its inner end fixed thereto and its outer end connected to a stationary part in said casing, and mechanism in said end space for transmitting motion between said rotatable member and the projecting part of said element.

8. Apparatus as set forth in claim 7 in which said mechanism in said end space for transmitting motion between said rotatable member and the projecting part of said element comprises gearing.

9. In a cordwinder, a frame, a cordwinding spool rotatably supported by said frame, said spool including axially spaced parallel flanges, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a driving drum having a cylindrical hub portion mounted for rotation coaxially with said spool adjacent to the outer face of one of said flanges, said drum having a third flange at the end of said hub remote from said one flange and axially parallel thereto, a spring storage drum rotatably supported by said frame to one side of and in radial alignment with said driving drum, the diameter of said storage drum being less than that of said driving drum and the periphery of the storage drum extending between said one flange and said third flange, and a spring prestressed to coil tightly around said storage drum and having its outer end secured to said hub portion of the driving drum to be wound thereon when said spool and driving rum are rotated by unwinding of said cord from said spool.

10. In a cordwinder, a frame, a cordwinding spool rotatably supported by said frame, said spool including axially spaced parallel flanges, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a driving drum having a cylindrical hub portion mounted for rotation coaxially with said l2 spool adjacent to the outer face of one of said flanges, said drum having a third flange at the end of said drum hub remote from said one flange and axially parallel thereto, said third flange having a diameter substantially less than that of said spaced flanges, a spring storage drum rotatably supported by said frame to one side of and in radial alignment with said driving drum, the diameter of said storage drum being less than that of said driving drum and the periphery of the storage drum extending inwardly beyond the periphery of said third flange, a spring prestressed to coil tightly around said storage drum and havin its outer end secured to said hub portion of the driving drum to be wound thereon when said spool and driving drum are rotated by unwinding said cord from said spool, and a flange on the end of said storage drum adjacent to said one of the spaced flanges.

11. In a cordwinder, a frame, a cordwinding spool rotatably supported by said frame, said spool including axially spaced parallel flanges one of which is made of insulating material and the other of metal, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a spring driving drum having a cylindrical hub portion mounted for rotation coaxially with said spool adjacent to the outer face of said metal flange, said drum having a third flange at the end of said drum hub remote from said metal flange and axially parallel thereto, a spring storage drum rotatably supported by said frame to one side of said driving drum, the diameter of said storage drum being less than that of said driving drum and said storage drum extending between said metal flange and said third flange to radially align said storage drum with said driving drum, a spring pie-stressed to coil tightly around said storage drum and having its outer end secured to said hub portion of the driving drum to be wound thereon when said spool and driving drum are rotated by unwinding of said cord from said spool, a pair of concentric slip rings mounted directly on said flange of insulating material, and a pair of brushes supported by said frame for frictionally contacting said slip rings to establish electrical connections therewith.

12. In a cordwinder, a casing having a tube extending therethrough to form a passage, a cordwinding spool rotatably mounted within said casing on said tube, said spool including axially spaced parallel flanges, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a driving drum having a cylindrical hub portion adjacent to the outer face of one of said flanges and mounted for rotation with said spool on said tube, said drum having a third flange at the end of said hub remote from said one flange and axially parallel thereto, a spring storage drum rotatably supported in said casing to one side of said driving drum, the diameter of said storage drum being less than that of said driving drum and said storage drum extending between said one of said flanges and said third flange to radially align said storage drum with said driving drum, and a spring prestressed to coil tightly around said storage drum and having its outer end secured to said hub portion of the driving drum to be Wound thereon when said spool and driving drum are rotated by unwinding of said cord from said spool.

13. In a cordwinder, a frame, a hub rotatably mounted on said frame and formed at one end with a flange integral therewith, an intermediate sheet metal flange carried by said hub in axially spaced parallel relation to the integral flange, a flange of insulating material at the other end of said hub in axially spaced parallel relation to said sheet metal flange, a cord windable between said sheet metal flange and said flange of insulating material, a spring storage drum rotatably mounted in said frame to one side of said hub and extending between said integral flange and said sheet metal flange to align said storage drum with the portion of said hub therebetween, the diameter of said storage drum being less than that of said portion of the hub, a spring prestressed to coil tightly around said storage drum and having its outer end secured to said portion of the hub to be wound thereon when said hub is rotated by unwinding of said cord therefrom, a pair of concentric slip rings mounted directly on said flange of insulating material, and a pair of brushes supported by said frame for frictionally contacting said slip rings to establish electrical connections therewith.

14. In a cordwinder, a casing having a tube extending therethrough to form a passage, a cordwinding spool rotatably mounted within said casing on said tube, said spool including axially spaced parallel flanges, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a driving drum having a cylindrical hub portion adjacent to the outer face of one of said flanges and mounted for rotation coaxially with said spool on said tube, said drum having a third flange at the end of said hub remote from said one flange and axially parallel thereto, a spring storage drum ro tatably supported in said casing to one side of said driving drum, the diameter of said storage drum being less than that of said driving drum and said storage drum extending between said one of said flanges and said third flange to radially align said storage drum with said driving drum, a spring prestressed to coil tightly around said storage drum and having its outer end secured to said hub portion of the driving drum to be wound therearound when said spool and driving drum are rotated by unwinding of said cord from said spool, and a pawl pivotally mounted on the radial face of said third flange which is remote from said one flange and engageable with a recess formed in the outer wall portion of said tube for restraining rotation of said spool and driving drum by said spring.

15. In a cordwinder, a frame, a cordwinding spool rotatably supported by said frame, said spool including axially spaced flanges one of which is made at least partly of insulating material and the other of metal, a cord connected to said spool to be wound thereon between the adjacent inner faces of said flanges, a spring driving drum having a cylindrical hub portion mounted for rotation coaxially with said spool adjacent to the outer face of said metal flange, said drum having a third flange at the end of said drum hub remote from said metal flange arid axially parallel thereto, a spring storage drum rotatably supported by said frame to one side of said driving drum, the diameter of said storage drum being less than that of said driving drum and said storage drum extending between said metal flange and said third flange to radially align said storage drum with said driving drum, a spring prestressed to coil tightly around said storage drum and having its outer end secured to said hub portion of the driving drum to be wound thereon when said spool and driving drum are rotated by unwinding of said cord from said spool, a pair of concentric slip rings mounted directly on said insulating material of said one flange, and a pair of brushes supported by said frame for frictionally contacting said slip rings to establish electrical connections therewith.

16. In a cordwinder, a frame, a hub rotatably mounted on said frame and formed at one end with a flange integral therewith, an intermediate metal flange carried by said hub in axially spaced parallel relation to the integral flange, a flange including a body of insulating material at the other end of said hub in axially spaced parallel relation to said metal flange, a cord windable between said metal flange and said flange including the body of insulating material, a spring storage drum rotatably mounted in said frame to one side of said hub and extending between said integral flange and said metal flange to align said storage drum with the portion of said hub therebetween, the diameter of said storage drum being less than that of said portion of the hub, a spring prestressed to coil tightly around said storage drum and having its outer end secured to said portion of the hub to be wound thereon when said hub is rotated by unwinding of said cord therefrom, a pair of concentric slip rings mounted directly on said body of insulating material, and a pair of brushes supported by said frame for frictionally contacting said slip rings to establish electrical connections therewith.

References Cited in the file of this patent UNITED STATES PATENTS 448,164 Reinmann Mar. 10, 1891 850,052 Reare Apr. 9, 1907 1,260,626 Berg Mar. 26, 1918 2,029,613 Edstrom Feb. 4, 1936 2,314,177 Tamarin Mar. 16, 1943' 2,323,275 Lofgren June 29, 1943 2,375,917 Gross May 15, 1945 2,672,304 Kaufman Mar. 16, 1954 2,673,694 Howell Mar. 30, 1954 2,719,600 Brace Oct. 4, 1955 2,764,255 Beede Sept. 25, 1956 2,814,358 Beede et a1. Nov. 26, 1957 2,848,731 Tamarin Aug. 26, 1958 2,869,801 Foster Jan. 20, 1959 2,888,093 Wahlborg et a1 May 26, 1959 2,948,913 Tamarin Aug. 16, 1960 3,011,033 Belicka et al Nov. 28, 1961 FOREIGN PATENTS 779,117 Great Britain July 17, 1957 

1. IN APPARATUS OF THE CLASS DESCRIBED, A HOLLOW CASING HAVING SPACED END WALLS, THE END WALLS RESPECTIVELY HAVING AN INLET AND AN OUTLET FOR AIR, MEANS COMPRISING A STATIONARY HOLLOW TUBE HAVING ONE END JOINED TO THE CASING AT THE OUTLET AND EXTENDING WITHIN SAID CASING TOWARD THE INLET, SAID TUBE DEFINING AT LEAST A PORTION OF AN AIR PASSAGEWAY BETWEEN THE INLET AND THE OUTLET, A HOLLOW ROTATABLE ELEMENT, A REEL FORMING A PART OF SAIS ROTATABLE ELEMENT AND HAVING SPACED SIDES, MEANS FOR MOUNTING SAID HOLLOW ELEMENT ON SAID TUBE FOR ROTATION THEREON ABOUT A FIRST STATIONARY AXIS WITH SAID REEL SPACED FROM THE END WALL HAVING THE OUTLET, ONE OF THE SIDES OF SAID REEL AND THE END WALL HAVING THE OUTLET DEFINING AN AXIALLY EXTENDING END SPACE IN SAID CASING WHICH IS DISPOSED ABOUT SAID TUBE AND INTO WHICH A PART OF SAID HOLLOW ELEMENT PROJECTS, AN ELECTRICAL CORD FOR SAID REEL WHICH MAY BE WOUND THEREON BETWEEN ITS SPACED SIDES, AND STRUCTURE OPERATIVELY ASSOCIATED WITH THE PROJECTING PART OF SAID HOLLOW ELEMENT TO IMPART ROTATING MOVEMENT TO SAID ELEMENT AND SAID REEL FOR WINDING THE CORD THEREON, SAID LAST-MENTIONED STRUCTURE INCLUDING A ROTATABLE MEMBER, MEANS AT THE END WALL HAVING THE OUTLET FOR MOUNTING SAID MEMBER FOR ROTATION IN SAID END SPACE ABOUT A STATIONARY SECOND AXIS SPACED FROM AND SUBSTANTIALLY PARALLEL TO THE FIRST AXIS ABOUT WHICH SAID HOLLOW ELEMENT ROTATES, AND AN ELONGATED FLAT SPRING WOUND ON SAID ROTATABLE MEMBER.
 9. IN A CORDWINDER, A FRAME, A CORDWINDING SPOOL ROTATABLY SUPPORTED BY SAID FRAME, SAID SPOOL INCLUDING AXIALLY SPACED PARALLEL FLANGES, A CORD CONNECTED TO SAID SPOOL TO BE WOUND THEREON BETWEEN THE ADJACENT INNER FACES OF SAID FLANGES, A DRIVING DRUM HAVING A CYLINDRICAL HUB PORTION MOUNTED FOR ROTATION COAXIALLY WITH SAID SPOOL ADJACENT TO THE OUTER FACE OF ONE OF SAID FLANGES, SAID DRUM HAVING A THIRD FLANGE AT THE END OF SAID HUB REMOTE FROM SAID ONE FLANGE AND AXIALLY PARALLEL THERETO, A SPRING STORAGE DRUM ROTATABLY SUPPORTED BY SAID FRAME TO ONE SIDE OF AND IN RADIAL ALIGNMENT WITH SAID DRIVING DRUM, THE DIAMETER OF SAID STORAGE DRUM BEING LESS THAN THAT OF SAID DRIVING DRUM AND THE PERIPHERY OF THE STORAGE DRUM EXTENDING BETWEEN SAID ONE FLANGE AND SAID THIRD FLANGE, AND A SPRING PRESTRESSED TO COIL TIGHTLY AROUND SAID STORAGE DRUM AND HAVING ITS OUTER END SECURED TO SAID HUB PORTION OF THE DRIVING DRUM TO BE WOUND THEREON WHEN SAID SPOOL AND DRIVING DRUM ARE ROTATED BY UNWINDING OF SAID CORD FROM SAID SPOOL. 